In electrosurgery or in electrosurgical procedures, (Joulean) heat is generated in tissue by the flow of electric current and on the basis of electrical resistance of tissue. As a result of the shape and arrangement of electrodes that are used in this process, the flow of current is localized as precisely as possible. The tissue through which current has flowed is atrophied or destroyed by the resulting heat. As a result, tissues can be stuck together, for example, or closed, and bleeding can be stanched.
High-frequency alternating currents are used as a rule in electrosurgery in order to prevent stimulation of nerves and other undesired side effects. The terms “electrosurgery” and “HF surgery” therefore are often used synonymously. Another term often used synonymously is that of electrocauterization.
In micro-invasive and other procedures, electrosurgical methods are used to atrophy large-surface tissues in order to seal vessels in a small area or to atrophy cut surfaces as early as the cutting or immediately thereafter. For these and other applications, different current density distributions in the tissue are advantageous and desired in each case. Medical staff, particularly physicians, can influence the current density distribution by using different-shaped electrodes or tools and through the way these electrodes are used.